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| United States Patent |
5,234,558
|
|
Kadokura
|
August 10, 1993
|
Electrically conductive circuit member, method of manufacturing the same
and electrically conductive paste
Abstract
An electrically conductive circuit member, a method for manufacturing the
same, and an electrically conductive paste in which the electrically
conductive circuit member has an electrically conductive circuit forming a
pattern on an insulating substrate. The electrically conductive circuit
includes an electrodeposited film containing electrically conductive
particles and resin which can be electrically deposited.
| Inventors:
|
Kadokura; Susumu (Sagamihara, JP)
|
| Assignee:
|
Canon Kabushiki Kaisha (Tokyo, JP)
|
| Appl. No.:
|
673072 |
| Filed:
|
March 21, 1991 |
Foreign Application Priority Data
| Mar 22, 1990[JP] | 2-69823 |
| Mar 22, 1990[JP] | 2-69824 |
| Mar 22, 1990[JP] | 2-69825 |
| May 09, 1990[JP] | 2-117497 |
| Current U.S. Class: |
204/485; 204/487; 205/118; 205/188 |
| Intern'l Class: |
C25D 013/12 |
| Field of Search: |
204/181.4,181.1,180.2
205/125,118,188
|
References Cited
U.S. Patent Documents
| 4579882 | Apr., 1986 | Kanbe et al. | 523/137.
|
| 4751172 | Jun., 1988 | Rodriguez et al. | 204/180.
|
| 4806200 | Feb., 1989 | Larson et al. | 156/652.
|
| 4844784 | Jul., 1989 | Suzuki et al. | 204/180.
|
| 4891069 | Jan., 1990 | Holtzman et al. | 205/125.
|
| 5004672 | Apr., 1991 | D'Ottavio et al. | 204/181.
|
| Foreign Patent Documents |
| 59-223763 | Dec., 1984 | JP.
| |
| 61-276979 | Dec., 1986 | JP.
| |
Primary Examiner: Niebling; John
Assistant Examiner: Mayekar; Kishor
Attorney, Agent or Firm: Fitzpatrick, Cella, Harper & Scinto
Claims
What is claimed is:
1. A method of manufacturing an electrically conductive circuit member
having an electrically conductive circuit in a pattern on an insulating
substrate comprising:
(a) forming a plating layer on said insulating substrate:
(b) forming a resist pattern corresponding to a circuit pattern on said
plating layer
(c) performing an electrodeposition, said plating layer serving as an
electrode, while simultaneously immersing said insulating substrate into
an electrically conductive paste comprising a resin and electrically
conductive particles, which are electrically deposited on said plating
player that does not contain the resist pattern to selectively form an
electrodeposited film comprising said resin and said electrically
conductive particles;
(d) conducting a heating and hardening of said electrodeposited film; and
(e) removing said plating layer from said insulating substrate except for
portions upon which the electrodeposited film has been formed.
2. A method of manufacturing an electrically conductive circuit member
according to claim 1, including forming said plating layer in a thickness
between about 0.1 .mu.m and 1 .mu.m.
3. A method of manufacturing an electrically conductive circuit member
according to claim 1, including forming said plating layer in a thickness
between about 0.1 .mu.m and 1 .mu.m.
4. A method of manufacturing an electrically conductive circuit member
according to claim 1, including conducting said heating process at a
temperature between about 90.degree. C. and 100.degree. C.
5. A method of manufacturing an electrically conductive circuit member
according to claim 1, including forming said electrodeposited film, which
has been subjected to said heating process, to contain said electrically
conductive particles in an amount of about 20 to 80 % by weight.
6. A method of manufacturing an electrically conductive circuit member
according to claim 1, including employing said electrically conductive
particles which are selected from the group consisting of powder prepared
by metallizing the surface of ceramic powder, powder prepared by
metallizing the surface of natural mica powder or mixture thereof.
7. A method of manufacturing an electrically conductive circuit member
according to claim 6, wherein the average particle size of said ceramic
powder is from about 0.1 to 7 .mu.m.
8. A method of manufacturing an electrically conductive circuit member
according to claim 6, wherein the average particle size of said natural
mica powder is from about 0.1 to 7 .mu.m.
9. A method of manufacturing an electrically conductive circuit member
according to claim 6, wherein said electrically conductive particles
further comprise superfine metal powder, the average particle size of
which is from about 0.01 to 5 .mu.m.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electrically conductive paste and an
electrically conductive circuit member of a printed circuit board for use
in an optical device such as cameras, office machines, audio products, OA
equipment, home electric products, meters and communication devices.
2. Description of the Prior Art
Hitherto, electrically conductive circuits have been formed in a solid
phase-gas phase system on an insulating substrate by an evaporation
method, an ion plating method, a CVD method and a sputtering method.
Electrically conductive circuits have also been formed in a solid
phase-liquid phase system by a plating method, a metal soldering method
and a metal-oxide solder method. Furthermore, these circuits have been
formed in a solid phase-solid phase system by a DC voltage application
method and a pressing and heating method.
However, the above-described conventional methods of forming a circuit
encounter the following problems:
The evaporation method and the sputtering method employed in a solid
phase-gas phase require use of an expensive vacuum apparatus. Further, the
type of the substrates which may be employed are limited, causing problems
such that the overall cost cannot be reduced and mass production cannot
easily be performed. Furthermore, since the circuit is formed at high
temperature, use of the above-described methods is limited to substrates
possessing sufficient heat resistance.
It is necessary for each of the plating methods, the metal soldering method
and the metal-oxide mixture soldering method to make the thickness of the
plating layer, which serves as the pattern, 18 .mu.m or greater.
Therefore, it takes an extended time to complete the film formation,
preventing satisfactory production levels. Therefore, the overall cost
cannot be reduced. Furthermore, the solder method is arranged in such a
manner that silver powder, amorphous carbon powder or graphite powder is
mixed with a binder such as phenol resin, epoxy resin, polyester resin or
acrylic resin so that a desired pattern is screen-printed via a mask.
However, that printing method encounters a problem in that the obtainable
resolution is 150 .mu.m or lower. Therefore, it cannot be employed in an
apparatus such as a lap top computer because the size, weight and
thickness cannot be reduced, or the circuit realized in the form of a
card. Further, another problem arises in that the displayed quality is
unsatisfactory and reproducibility is insufficient. For example, bleeding,
blurs and insufficiency of the functional component, which take place in
the printed film cannot be prevented. Finally, since the screen mask
pattern can be undesirably plugged, the quality will be deteriorated.
In addition, the thickness of the formed film cannot be equalized if the
squeezing pressure or the squeezing speed is changed. In consequence,
sharp forms cannot be realized and the reproducibility also becomes
unsatisfactory, causing reduced quality of the product.
Furthermore, a satisfactory positional accuracy cannot be obtained in the
printing pattern, and the high temperature of 150.degree. C. or higher is
necessary to harden the film. Therefore, the substrate will become warped
or twisted, and a dimensional problem exists, causing deterioration of the
ability and efficiency of connection to the adjoining parts when
assembled. As a result, a critical problem arises in that the cost cannot
be reduced and a satisfactory efficiency in the mass production cannot be
realized.
Furthermore, since the above-described paste contains a toxic organic
solvent, a risk of contaminating the working space or fire hazard cannot
be overcome.
The high melting metallizing method is usually employed in the solid
phase-solid phase system. However, that method forms the circuit at high
temperature similarly to the solid phase-gas phase method. Therefore, the
application is limited to a substrate such as a ceramic plate which
reveals sufficient heat resistance and dimensional stability.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an
electrically conductive circuit member the thickness of which can be
reduced and which reveals a satisfactory adhesion of the circuit to the
substrate and satisfactory electrical conductivity.
Another object of the present invention is to provide a method of
manufacturing an electrically conductive circuit member having an
extremely precise circuit pattern formed thereon while maintaining an
excellent positional accuracy.
Another object of the present invention is to provide electrically
conductive paste revealing an excellent electrical conductivity and it can
thereby be used to form a fine pattern circuit.
Another object of the present invention is to provide electronic equipment
the size and the weight of which can be reduced and which is free from the
occurrence of defects in the electrically conductive circuit thereof.
According to one aspect of the present invention, there is provided an
electrically conductive circuit member having an electrically conductive
circuit forming a pattern on an insulating substrate, the electrically
conductive circuit member comprising: an electrodeposited film containing
electrically conductive particles and resin which can be electrically
deposited.
According to another aspect of the present invention, there is provided a
method of manufacturing the above-described electrically conductive
circuit member having an electrically conductive circuit in a pattern on
an insulating substrate comprising performing an electrodeposition while
simultaneously immersing an insulating substrate into electrically
conductive paste containing a resin and electrically conductive particles,
which can be electrically deposited onto the surface of the insulating
substrate to selectively form on said insulating substrate an
electrodeposited film containing the resin and the electrically conductive
particles; and conducting a heating and hardening process.
According to another aspect of the present invention, there is provided
electrically conductive paste comprising: from about 3 to 50 wt % of a
resin which can be electrically deposited; and from about 4 to 80 wt % of
electrically conductive particles.
According to another aspect of the present invention, there is provided
electronic equipment comprising: an electrically conductive circuit member
having an electrically conductive circuit forming a pattern on an
insulating substrate; said electrically conductive circuit member
comprising an electrodeposited film which contains resin which can be
electrically deposited and electrically conductive particles.
An electrodeposited film is formed by simultaneous deposition of the resin
and the electrically conductive particles only on the circuit pattern as a
result of the electrodeposition. Therefore, an excellent circuit
substrate, revealing a uniform thickness of the formed film can be
obtained while preventing defects such as bleeding, blurrs and deficiency
of a necessary component of the circuit.
Furthermore, since the electrically conductive particles deposit in the
electrodeposited film at high density, the electric characteristics can
further be improved. In addition, since the circuit pattern is formed by a
photolithographic process, a circuit substrate having an extremely precise
circuit pattern formed thereon can be obtained.
In addition, since the resin and the electrically conductive particles are
deposited due to electrophoresis, a desired film can be formed by smaller
energy and in a shorter time in comparison to plating method. Therefore,
an electrically conductive circuit member having a precise pattern formed
thereon and revealing excellent physical properties can easily be
manufactured.
Other objects, features and advantages of the invention will be appear more
fully from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an embodiment of a method of manufacturing an
electrically conductive circuit member according to the present invention;
FIG. 2 illustrates another embodiment of the method of manufacturing an
electrically conductive circuit member according to the present invention;
FIG. 3 is an enlarged view which illustrates an electrodeposited film which
forms the electrically conductive circuit member according to the present
invention; and
FIG. 4 is a schematic cross sectional view which illustrates electronic
equipment which employs the circuit member according to the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will now be described with
reference to the drawings.
FIGS. 1A to 1E illustrate an example of a method of manufacturing an
electrically conductive circuit member according to the present invention.
Referring to FIG. 1, a catalytic layer 2 is formed on an insulating
substrate 1 by a catalytic process. Successively, an electroless plating
layer 3 is formed on the catalytic layer 2 by electroless plating (see
FIG. 1A).
Subsequently, the electroless plating layer 3 is coated with a
photosensitive resin 4 before a light beam 7 is applied thereto via a
pattern mask 8 (see FIG 1B). A resist pattern corresponding to a desired
circuit pattern is formed after a development process has been performed
(see FIG. 1C). Then, the insulating substrate 1, having the
above-described resist pattern formed thereon, is immersed into an
electrically conductive paste which contains a resin and electrically
conductive particles so as to be subjected to electrophoresis, the resin
being electrically depositable. In consequence, an electrodeposited layer
5 is formed (see FIG. 1D). Subsequently, the thus processed substrate is
heated so that the electrodeposited film 5 is hardened before the
photosensitive resin 4 is separated from the substrate. Then, the plating
layer 3 formed in portions, except for the portions on which the
electrodeposited film 5 has been formed, is removed by etching so that an
electrically conductive circuit member according to the present invention
and having a circuit 6, the major portion of which is made of the
electrodeposited film 5, can be obtained (see FIG. 1E).
The circuit according the present invention is formed by the
electrodeposited film 5 which has deposited a high density of the
electrically conductive particles together with the resin which can be
electrically deposited. In consequence, a circuit thus formed reveals an
excellent electrical conductivity and a precise structure with a
satisfactory positional accuracy, although its thickness is reduced since
it can be formed by photolithography. Furthermore, the present invention
is different from conventional methods in that the electrically depositing
process is employed. Therefore, the film having a constant thickness can
be formed at low voltage.
The present invention is not limited to the electrically conductive
particles serving as the eutectoid formed on the electrodeposited film.
However, it is preferable to use powder (hereinafter called "metallized
ceramic powder") manufactured by plating a metal on the surface of ceramic
powder or powder (hereinafter called "metallized natural mica" or
"metallized mica powder") manufactured by plating a metal on the surface
of natural mica powder. The reason for this is that the electrodeposited
film can be perfectly hardened by a low temperature of from about
90.degree. C. to 100.degree. C. The reason why the electrodeposited film
containing the above-described powder can be hardened at the low
temperature has not been discovered. However, it can be considered that
the metallized ceramic or the metallized natural mica powder enables the
electrodeposited film to be easily hardened because the metallized ceramic
and the metallized natural mica powder can stably maintain the active
surfaces of the particles, in a different manner from the ordinary metal
powder which is easily oxidized on its surface, the active surfaces of the
particles serve as crosslinking points at the time of the hardening
operation. The metallized natural mica or the metallized ceramic powder
may comprise powder formed by plating a metal, for example, Ag, Ni, Cu, Au
or Sn to the surface of the ceramic particles.
The preferable average particle size of the ceramic power and the natural
mica powder is from about 0.1 to 7 .mu.m, preferably about 0.5 to 5 .mu.m,
when measured by a centrifugal decanter SACP-3 manufactured by Shimazu, in
order to the facilitate the dispersion of the powder in the electrically
conductive paste.
The ceramic according to the present invention is exemplified by aluminum
oxide, titanium nitride, manganese nitride, tungsten nitride, tungsten
carbide, lanthanum nitride, aluminum silicate, molybdenum disulfide,
titanate oxide, graphite and silicic acid. The natural mica is exemplified
by phologopite, sericite and muscovite.
It is preferable to use nickel or copper to apply as the plating on the
surface of the ceramic powder or the natural mica so that the sealing
performance is improved. Furthermore, it is preferable to employ an
electroless plating method to plate the surface of the ceramic. The
thickness of the plating to be applied to the surface of the powder should
be from about 0.05 to 3 .mu.m, preferably about 0.15 to 2 .mu.m so that
excellent sealing performance can be obtained and as well as satisfactory
physical properties can be displayed when it is hardened at low
temperature. That is, if the thickness of the plating is larger than 3
.mu.m, the displayed characteristics of the surface becomes similar to
those of the metal particles which display an extremely low activity.
Therefore, the surface is oxidized in air, causing the number of the
active points engaging in crosslinking to be reduced. In consequence, the
electrodeposited film cannot satisfactorily be hardened or heated when it
is burned or heated at low temperature.
The quantity of the electrically conductive particles contained in the
electrodeposited film serving as the circuit of the electrically
conductive member according to the present invention is arranged to be
from about 20 to 80 wt %, preferably about 20 to 50 wt % so as to obtain
excellent electrical conductivity and to enable the coated film to have
satisfactory physical properties, and, in particular, to realize excellent
contact with the base material.
The quantity of the metallized ceramic powder can be measured by using an
X-ray microanalyzer and an analysis performed in accordance with a
thermogravimetric analysis for example, performed on PERKIN-ELMER; Thermal
Analysis System 7 Series.
The structure according to the present invention may be arranged in such a
manner that both the metallized ceramic powder and the metallized natural
mica powder are contained in the electrodeposited film at a mixture ratio
which is not limited but both together must be included in the
above-described range of the electrically conductive particles in the
electrodeposited film. However, it is preferable to make the mixture ratio
of the metallic ceramic powder and the metallic mica powder be about 1:1
to 2.5.
Furthermore, superfine metal powder, the average particle size of which is
from about 0.01 .mu.m to 5 .mu.m, may be added tot eh electrodeposited
film in addition to the metallized ceramic powder and/or the metallized
mica powder. The present invention is not limited to the type of the
superfine metal powder. However, it is exemplified by Ag, Co, Cu, Fe, Mn,
Ni, Pd, Sn and Te. It is preferable that the average particle size of the
superfine metal powder by about 0.01 to 5 .mu.m, preferably about 0.02 to
5 .mu.m, and more preferably, it is about 0.03 to 0.08 .mu.m. If it is
smaller than about 0.01 .mu.m, undesirable secondary aggregation will take
place. If it is larger than about 5 .mu.m, the amount of precipitation
makes it unsatisfactory. The above-described superfine metal powder can be
manufactured by using a heat plasma evaporation method. The mixture ratio
of metallized ceramic powder and/or the metallized natural mica and the
superfine metal powder is from about 1:0.2 to 3.0, preferably about 1:0.3
to 2.5 so that a gap formed between the metallized ceramic and/or the
metallized natural mica 31 is, as shown in FIG. 3, filled with superfine
metal powder 32. In consequence, the contact areas between the particles
are enlarged, causing the electrically conductivity to further be
improved. However, if the quantity of the superfine metal powder to be
contained is further increased, the quantity of the metallized ceramic
and/or the metallized mica contained in the electrodeposited film is
relatively reduced. In consequence, the contact areas between the
particles are reduced and the electrical conductivity is thereby
deteriorated. Therefore, the formed film does not display the desired
physical properties when it is hardened at low temperature. In a case
where the electrical conductivity desired by the electrically conductive
circuit, for example, a specific resistance (.OMEGA..multidot.cm) of an
order of 10.sup.-3, preferably 10.sup.-5 is realized, the quantity of the
superfine metal powder to be contained must be increased. In this case,
the weight ratio of the superfine metal powder with respect to the resin
which can be electrically deposited is excessively increased. As a result,
the physical properties of the formed film, such as the contact and
adhesion to the base material is deteriorated.
When the superfine metal powder is added as described above, it is
preferably to activate the surface of the superfine metal powder such
that, for example, the oxidized film on the surface of the powder is
removed. As an alternative to this, it is effective to process the surface
of the superfine metal powder with a surface active agent.
The resin which can be electrically deposited according to the present
invention may be ordinary resin which has heretofore been used in
electrodeposition. It is exemplified by a resin of a type which is
hardened due to a reaction with a hardening agent, for example,
acrylmelamine resin, acrylic resin, epoxy resin, urethane resin and alkyd
resin. Furthermore, a resin of a type which can be hardened due to a
reaction of a double bond in a molecule, for example, a polybutadiene
resin and an .alpha., .beta. ethylenically unsaturated compound is
exemplified.
It is preferable to make the thickness of the electrodeposited film from
about 7 to 20 .mu.m.
A method of manufacturing the circuit member according to the present
invention will now be described in detail.
According to the present invention, an insulating base 1 is made of a resin
material or an inorganic material, the resin material being exemplified by
a film or a plate made of polyester, acrylic, polyamide, phenol, epoxy or
polyimide resin. The inorganic material is exemplified by a ceramic plate.
The resin base can preferably be used to form a flexible printed circuit
or a multilayer printed circuit board, while the ceramic plate can
preferably be used to form a hybrid integrated circuit (IC) substrate.
The thus manufactured insulating substrate is subjected to a catalytic
process in accordance with a known method before the electroless plating
is applied to form the plating layer 3. However, it is preferable to
roughen its surface in order to improve the contact with the insulating
substrate before the catalytic process is performed. A method of
roughening the surface is exemplified by a treatment with caustic soda, or
a mixed solution of chromic acid and sulfuric acid or an organic solvent,
a blast process and a liquid honing process.
As the catalytic process, a palladium process can be employed.
The electroless plating may use gold, silver, palladium, nickel, copper,
tin and zinc. However, it is preferable to employ copper since it reveals
a satisfactory conductivity, the electrodeposited film 6 can easily be
adhered to it and its cost can be reduced. Since the plating layer 3
serves as an electrode at the time of the electrodeposition, it is
preferable that the thickness be between about 0.1 .mu.m and 1 .mu.m. If
the thickness is larger than 1 .mu.m, it takes too long to form the
plating layer 3, and, an excessively long time elapses for an ensuing
separation process to be completed.
Then, the plating layer 3 is coated with a known photosensitive resin,
preferably a dry film or a liquid resist or the like made of a negative or
positive type photosensitive resin having an aspect ratio of 1.5 or more.
The thickness of the photosensitive resin is determined depending upon a
desired density of the circuit, the thickness of the conductor of the
circuit and the like. The exposure of the pattern can be performed by
using an ordinary glass mask or a film mask and an exposing machine
emitting parallel beams or scattered light. The luminous quantity
(mJ/cm.sup.2) and whether the parallel beams are employed or the scattered
light is used are determined depending upon the desired density of the
circuit.
Then, a developer which is used to develop photosensitive resin is used to
perform the development process. As a developer, for example,
trichloroethane is used to develop a solvent type photosensitive resin,
while sodium carbonate or the like is used to develop water soluble
photosensitive resin.
Subsequently, the base material on which a resist pattern which corresponds
to the circuit pattern is immersed in the electrically conductive paste so
that the electrodeposition is performed. Then, the electrodeposited film 6
is formed on the exposed plating layer 3 by the electrophoresis.
The above-described electrodeposition process can be performed in
accordance with an ordinary electrodeposition coating method which is
carried out in such a manner that the substance to be coated, that is, the
base material is made to be the positive pole when anion electrodeposition
coating is performed. When cation electrodeposition coating is performed
by making the base material the negative pole, a stainless steel plate is,
for example, used to serve as the opposite pole electrode. The
electrodeposition conditions are determined depending upon the density of
the electrically conductive particles contained in the electrically
conductive paste and the desired characteristics (electrical conductivity,
the physical properties of the formed film and the thickness of the formed
film) of the electrodeposited film. However, usually, the liquid
temperature is about 20.degree. to 27.degree. C., the pH value is about
8.0 to 9.5, voltage to be applied is about 50 to 200 V and the duration of
treatment is about 1 to 5 minutes.
After the electrodeposited film has been formed, it is washed with water
and is heated so that the electrodeposited film is hardened.
The oven in which the electrodeposited film can be hardened is held at a
low temperature of about 90.degree. C. to 100.degree. C. for about 20 to
180 minutes, in a case where the electrically conductive particles are the
metallized ceramic powder and/or the metallized natural mica. In a case
where ordinary metal powder is used, it is preferable to heat it at about
120.degree. C. to 170.degree. C.
Then, a separating liquid, which can be used to separate the photosensitive
resin, is used to separate the photosensitive layer formed on the plating
layer 3. The solvent type photosensitive resin is separated by, for
example, methylene chloride or an exclusive separating liquid chosen in
accordance with the photosensitive resin used. On the other hand, the
water soluble photosensitive resin is separated by, for example, from
about 1 to 5 wt % caustic soda. Subsequently, the exposed plating layer 3
is removed by an ammonical alkaline copper solution or a ferric chloride
solution. As a result, an electrically conductive circuit member 11 on
which the circuit is formed by the electrically conductive
electrodeposited film can be manufactured.
As described above, the method of manufacturing a circuit member according
to the present invention is capable of manufacturing a precise circuit
substrate, the pattern of which has a pitch on the order of, for example,
1 .mu.m to several tens of micrometers, which can easily be manufactured
while revealing an excellent positional accuracy since its circuit pattern
is manufactured by the photolithographic method.
The electrically conductive paste component of electrically conductive
circuit member according to the present invention will be described below.
The electrically conductive paste according to the present invention can be
prepared by dispersing, in a ball mill for 24 to 35 hours, electrically
conductive particles or a resin which can be electrically deposited. It is
then diluted with salt water so as to adjust the density of the solid
component to be about 60 to 90 wt %.
The quantity of the electrically conductive particles contained in the
electrically conductive paste is made to be about 4 to 80 wt %, preferably
7 to 70 wt % so that the electrically conductive particles are of such a
quantity which is sufficient to give the electrodeposited film a
predetermined electrical conductivity. Furthermore, the precipitation of
the electrically conductive particles in the paste can be prevented. The
electrically conductive paste contains from about 3 to 50 wt %, preferably
5 to 40 wt % of the resin, which can be electrically deposited so that an
electrodeposited film revealing satisfactory physical properties can be
formed.
As the electrically conductive particles to be dispersed in the
electrically conductive paste, the powder which the eutectoid resin in the
electrically conductive film can be used, for example, the above-described
metallized ceramic powder and/or the metallized natural mica powder and a
material prepared by adding the superfine metal powder, the average
particle size of which is 0.01 to 5 .mu.m to the metallized ceramic powder
and/or the metallized natural mica powder.
FIGS. 2A to 2E illustrate another embodiment of the method of manufacturing
the electrically conductive circuit member according to the present
invention. Referring to FIG. 2, the insulating substrate 1 is subjected to
a known catalytic process so that the catalyst layer 2 is formed (see FIG.
2A).
Subsequently, the photosensitive resin 4 is applied before it is exposed to
light 7 via the pattern mask 8 (see FIG. 2B). Then, the latent image is
developed so that a resist pattern corresponding to a circuit pattern is
formed (see FIG. 2C).
Then, the electroless plating is applied to the resist pattern, so that the
electroless plating layer 3 is formed. The electrically conductive paste
film is then formed by electrophoresis by using the electrically
conductive paste 5 (see FIG. 2D).
Subsequently, the photosensitive resin 4 except for the circuit pattern
portion is separated so that the electrically conductive circuit member
according to the present invention can be obtained (see FIG. 2E).
According to the method shown in FIG. 2, the conditions necessary for each
of the processes shown in FIG. 1 can be used.
As described above, the electrically conductive circuit member according to
the present invention has the electrodeposited film formed on the circuit
pattern by the electrodeposition coating method by using the electrically
conductive paste liquid. As a result, problems in terms of the
non-uniformity, occurrences of bleeding, blurs and insufficiency of
necessary components can be overcome. Furthermore, the electric
characteristics can be significantly improved so that a member revealing
an excellent reproducibility can be formed.
Furthermore, according to the present invention, the electrodeposited layer
is formed while forming the circuit pattern by the photolithography
process. Therefore, an electrically conductive circuit member having an
extremely precise circuit pattern can be easily manufactured. In addition,
a desired electrical conductivity can be realized even if the thickness of
the electrodeposited film is considerably reduced. Furthermore, an
electrically conductive circuit member such as a printed circuit board the
size and weight of which are minimized can be manufactured. As a result,
the present invention can effectively be applied to electronic equipment.
Furthermore, according to the present invention, in the case where the
metallized ceramic powder or the metallized natural mica powder is used as
the electrically conductive particles, an electrodeposited film revealing
excellent physical properties can be formed even if the heating is
performed at a relatively low temperature of 90.degree. C. to 100.degree.
C. Therefore, a precise circuit can be formed on an insulating substrate,
the heat resistance of which is insufficient to endure treatment at higher
temperatures, or a thin flexible substrate can be used. As a consequence,
an electrically conductive circuit member which can effectively be applied
to small and light weight electronic equipment can be obtained. For
example, as shown in FIG. 4, a substrate 1 has a circuit substrate having
a circuit formed by the electrodeposited film 6 on which an electronic
part 42 such as IC. is mounted. Then, that substrate is fixed to a frame
41 so that form factor piece of electronic equipment 43 can be
manufactured. Reference numeral 44 represents an electrode of the
electronic part.
Furthermore, the overall cost can significantly be reduced since the
manufacturing process can be simplified.
EXAMPLES
Examples of the present invention will now be described. However, the
present invention is not limited to the examples.
EXAMPLE 1-1
A PET (Polyethylene Terephthalate) film having a thickness of 50 .mu.m was
treated with 50 g/l of caustic soda at 60.degree. C. for 5 minutes. Then,
the PET film was treated with a mixed solution of 30 g/l of chromic
anhydride and 100 g/l of sulfuric acid at 50.degree. C. for 5 minutes.
Subsequently, it was immersed in a catalyst liquid (trade name "HS-101B"
prepared by Hitachi Kasei) for 2 minutes so that it was subjected to the
catalyst process. Then, nonelectrolytic copper plating liquid (prepared by
Okuno) was applied with a plating bath at a temperature of 70.degree. C.
and pH value of 13.0, for 5 minutes. In consequence, a copper plating
layer having a thickness of 0.2 .mu.m was formed.
Then, a photosensitive dry film (manufactured by Hoechst A.G.) having a
thickness of 70 .mu.m, was applied to the surface of the plating layer on
the PET film by using a laminator (manufactured by Asahi Kasei).
Subsequently, a film mask serving as the pattern mask was used to expose
the PET film to light at an intensity of 120 mJ/cm.sup.2, before it was
developed by spraying with 10 g/l of sodium carbonate. In consequence, a
pattern was formed corresponding to a circuit pattern arranged in such a
manner that the width of the exposed plating layer was 40 .mu.m and that
of the coated portion of the photosensitive layer was 50 .mu.m.
Then, a voltage of 170 V was applied for 3 minutes in an electrically
conductive paste prepared by dispersing 25 wt % of desalinated water, 5 wt
% of melamine acryl resin (trade name "Honey Bright C-IL" manufactured by
Honey Kasei) and 70 wt % of powder formed by applying nickel plating to
form a thickness of 0.2 .mu.m to the surface of alumina, the average
particle size of which was 1.0 .mu.m, the voltage being applied while
making the substrate serve as the positive pole and using a stainless
steel electrode (0.5 t) to serve as the opposite pole, at a bath
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before being heated in an oven at 95.degree. C..+-.1.degree. C. for
90 minutes, so as to be hardened.
The film thickness was 25 .mu.m and the density of the metallized ceramic
powder was 50 wt % at that time. Then, it was immersed in 50 g/l of
caustic soda at 40.degree. C. for 5 minutes so that the photosensitive
resin was separated. Subsequently, ammonic alkaline copper liquid was used
to remove the copper plating film on the exposed portion at 50.degree. C.
for 7 minutes so that a fine printed circuit board was obtained.
In order to evaluate the performance of the thus manufactured circuit, the
initial values and values after environmental testing of the specific
resistance, the surface resistance and the adhesion were measured. The
results are as shown in Table 1.
As a comparative example 1, a circuit member using a conventional organic
solvent type electrically conductive paste was also evaluated, the pitch
between the circuits being 100 .mu.m and the width of the circuit being
100 .mu.m.
An adhesion test was performed in conformity with JIS K5400 cross-cut
adhesion test in such a manner that 100 cross-cut squares were made so as
to be subjected to a separation test by using a cellophane tape and the
resulting states of the squares were observed. The specific and surface
resistances were measured by a superinsulating resistance measuring device
(trade name HP4329A manufactured by Yokokawa). The results are as shown in
Table 1-1.
TABLE 1-1
______________________________________
Results of the evaluations of the
electrically conductive circuit members
After 1000 hours
Initial Value at 55.degree. C. .times. 95% RH
Com- Com-
parative parative
Tests Example 1 Example 1 Example 1
Example 1
______________________________________
Adhesion
100/100 100/100 100/100 90/100
Specific
5 to 6 .times.
1.0 to 1.3 .times.
2% or Less
2% or Less
Resistance
10.sup.-5 .OMEGA.-cm
10.sup.-4 .OMEGA.-cm
(Resistance
(Resistance
(25.degree. C.) Change) Change)
Surface 5 .times. 20
50 .times. 100
2% or Less
2% or Less
Resistance
m.OMEGA./square
m.OMEGA./square
(Resistance
(Resistance
(25.degree. C.) Change) Change)
______________________________________
As shown in Table 1-1, a significant improvement was realized in comparison
to the conventional circuit substrate while revealing a sufficient
reproducibility.
The circuit according to Comparative Example 1 encountered a problem in
terms of a partial bleeding generated in the printed film and a short
circuit occurred when the circuit pitch was 100 .mu.m. Furthermore, a
pattern having a pitch smaller than 100 .mu.m could not be manufactured by
the printing method.
EXAMPLE 1-2
An alumina ceramic plate having a thickness of 0.4 mm was subjected to
blasting to an extent such that its surface was not damaged. Subsequently,
the alumina ceramic plate was treated with a mixed solution of 30 g/l of
chromic anhydride and 100 g/l of sulfuric acid at 50.degree. C. for 5
minutes. Subsequently, it was immersed in a catalyst liquid (trade name
"HS-101B" prepared by Hitachi Kasei) for 2 minutes so that it was
subjected to the catalyst process. Then, nonelectrolytic copper plating
liquid (prepared by Okuno) was used so that it was applied by plating in a
plating bath with a temperature of 70.degree. C. and pH value of 13.0 for
3 minutes. In consequence, a copper plating layer having a thickness of
0.1 .mu.m was formed.
Then, a photosensitive dry film (manufactured by Hoechst A.G.) having a
thickness of 35 .mu.m was applied to the surface of the plating layer on
the alumina ceramic plate by using a laminator (manufactured by Asahi
Kasei). Subsequently, a film mask serving as the pattern mask was used to
expose the alumina ceramic plate to light at an intensity of 100
mJ/cm.sup.2 before it was developed by spraying with 10 g/l of sodium
carbonate. In consequence, a pattern corresponding to a circuit pattern
arranged in such a manner that the width of the exposed plating layer was
30 .mu.m and that of the coated portion of the photosensitive layer was
40 .mu.m was formed.
Then, a voltage of 180 V was applied for 3 minutes in an electrically
conductive paste prepared by dispersing 55 wt % of desalinated water, 5 wt
% of melamine acryl resin (trade name "Honey Bright C-IL" manufactured by
Honey Kasei) and 40 wt % of powder formed by applying a nickel plating to
form a layer thickness of 0.5 .mu.m on the surface of alumina, the average
particle size of which was 1.0 .mu.m, the voltage being applied while
making the substrate serve as the positive pole and using a stainless
steel electrode (0.5 t) to serve as the opposite pole in a bath at a
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before being heated in an oven at 95.degree. C..+-.1.degree. C. for
90 minutes so as to be hardened. The film thickness was 30 .mu.m and the
density of the metallized ceramic powder was 60 wt % at that time. Then,
it was immersed in 50 g/l of caustic soda at 40.degree. C. for 5 minutes
so that the photosensitive resin was separated. Subsequently, ammonic
alkaline copper liquid was used to remove the copper plating film on the
exposed portion at 50.degree. C. for 7 minutes so that a fine printed
circuit board was obtained.
The characteristics of the thus manufactured substrate were evaluated by
the same method according to Example 1. The results are as shown in Table
1-2.
EXAMPLE 1-3
A polyimide film having a thickness of 18 .mu.m was treated with 50 g/l of
caustic soda at 60.degree. C. for 5 minutes. Subsequently, the polyimide
film was treated with a mixed solution of 30 g/l of chromic anhydride and
100 g/l of sulfuric acid at 50.degree. C. for 5 minutes. Subsequently, it
was immersed in a catalyst liquid (trade name "HS-101B" prepared by
Hitachi Kasei) for 2 minutes so that it was subjected to the catalyst
process. Then, electroless copper plating liquid (prepared by Okuno) was
applied with the plating bath at the temperature of 70.degree. C. and pH
value of 3.0 for 3 minutes. In consequence, a copper plating layer having
a thickness of 0.1 .mu.m was formed.
Then, a photosensitive dry film (manufactured by Hoechst A.G.) having a
thickness of 50 .mu.m was applied to the surface of the plating layer on
the polyimide film by using a laminator (manufactured by Asahi Kasei).
Subsequently, a film mask serving as the pattern mask was used to expose
the polyimide film to light at an intensity of 90 mJ/cm.sup.2 before it
was developed by spraying with 10 g/l of sodium carbonate. In consequence,
a pattern was formed corresponding to a circuit pattern arranged in such a
manner that the width of the exposed plating layer was 35 .mu.m and that
of the coated portion of the photosensitive layer was 50 .mu.m.
Then, a voltage of 170 V was applied for 3 minutes in an electrically
conductive paste prepared by dispersing 15 wt % of desalinated water, 5 wt
% of melamine acryl resin (trade name "Honey Bright C-IL" manufactured by
Honey Kasei) and 80 wt % of powder formed by applying nickel plating to
form a thickness of 0.2 .mu.m on the surface of alumina, the average
particle size of which was 1.0 .mu.m, the voltage being applied while
making the substrate serve as the positive pole and using a stainless
steel electrode (0.5 t) to serve as the opposite pole at a bath
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before being heated in an oven at 95.degree. C..+-.1.degree. C. for
90 minutes so as to be hardened. The film thickness was 25 .mu.m and the
density of the metallized ceramic powder was 50 wt % at that time. Then,
it was immersed in 50 g/l of caustic soda at 40.degree. C. for 5 minutes
so that the photosensitive resin was separated. Subsequently, ammonic
alkaline copper liquid was used to remove the copper plating film on the
exposed portion at 50.degree. C. for 7 minutes so that a fine printed
circuit board was obtained.
The characteristics of the thus manufactured circuit substrate were
evaluated by the same method according to Example 1.
EXAMPLE 1-4
A beryllia ceramic plate having a thickness of 0.8 mm was subjected to
blasting to such an extent that its surface was not damaged. Subsequently,
the beryllia ceramic plate was treated with a mixed solution of 30 g/l of
chromic anhydride and 100 g/l of sulfuric acid at 50.degree. C. for 5
minutes. Subsequently, it was immersed in a catalyst liquid (trade name
"HS-101B" prepared by Hitachi Kasei) for 2 minutes so that it was
subjected to the catalyst process. Then, electroless copper plating liquid
(prepared by Okuno) was applied with the temperature of the plating bath
at 70.degree. C. and a pH value of 13.0 for 3 minutes. In consequence, a
copper plating layer having a thickness of 0.2 .mu.m was formed.
Then, a negative type resist (trade name "OMR-83" manufactured by Tokyo
Ouka) 450 cp was used so that a film having a thickness of 10 .mu.m was
formed by a spinner. Subsequently, a glass mask with a chromium pattern
serving as the pattern mask was used to expose the beryllia ceramic plate
to light at an intensity of 80 mJ/cm.sup.2 by an exposing device which
emits parallel beams before it was developed by an exclusive developer
(manufactured by Tokyo Ouka) for OMR-83 for one minute. In consequence, a
pattern was formed corresponding to a circuit pattern arranged in such a
manner that the width of the exposed plating layer was 25 m and that of
the coated portion of the photosensitive layer was 30 .mu.m.
Then, a voltage of 120 V was applied for 3 minutes in an electrically
conductive paste prepared by dispersing 67 wt % of desalinated water, 3 wt
% of melamine acryl resin (trade name "Honey Bright C-IL" manufactured by
Honey Kasei) and 30 wt % of a powder formed by applying nickel plating to
form a thickness of 0.2 .mu.m to the surface of alumina the average
particle size of which was 1.0 .mu.m. The voltage was applied while making
the substrate serve as the positive pole and using a stainless steel
electrode (0.5 t) to serve as the opposite pole at a bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C..+-.1.degree. C. for 90 minutes so
as to be hardened. The film thickness was 18 .mu.m and the density of the
metallized ceramic powder was 30 wt % at that time. Then, it was immersed
in an exclusive separation liquid for OMR (manufactured by Tokyo Ouka) at
40.degree. C. for 5 minutes so that the photosensitive resin was
separated. Subsequently, ammonic alkaline copper liquid was used to remove
the copper plating film on the exposed portion at 50.degree. C. for 7
minutes so that a fine printed circuit board was obtained.
The characteristics of the thus manufactured substrate were evaluated by
the same method according to Example 1.
EXAMPLE 1-5
A PET (Polyethylene Terephthalate) film having a thickness of 50 .mu.m was
treated with 50 g/l of caustic soda at 60.degree. C. for 5 minutes. Then,
the PET film was treated with a mixed solution of 30 g/l of chromic
anhydride and 100 g/l of sulfuric acid at 50.degree. C. for 5 minutes.
Subsequently, it was immersed in a catalyst liquid (trade name "HS-101B"
prepared by Hitachi Kasei) for 2 minutes so that it was subjected to the
catalyst process.
Then, a photosensitive dry film (manufactured by Hoechst A.G.) having a
thickness of 70 .mu.m was applied to the surface of the PET film by using
a laminator (manufactured by Asahi Kasei). Subsequently, a film mask
serving as the pattern mask was used to expose the PET film to light at an
intensity of 120 mJ/cm.sup.2, before it was developed by spraying with 10
g/l of sodium carbonate. In consequence, a pattern was formed
corresponding to a circuit pattern arranged in such a manner that the
width of the exposed plating layer was 40 .mu.m and that of the coated
portion of the photosensitive layer was 50 .mu.m.
Subsequently, electroless copper plating liquid (prepared by Okuno) was
used for plating a temperature of 70.degree. C. at and a pH value of 13.0
for 2 minutes so that copper plating having a thickness of 0.1 .mu.was
performed.
Then, a voltage of 170 V was applied for 3 minutes in an electrically
conductive paste prepared by dispersing 15 wt % of desalinated water, 5 wt
% of melamine acryl resin (trade name "Honey Bright C-IL" manufactured by
Honey Kasei) and 80 wt % of powder formed by applying nickel plating to
form a layer of thickness 0.2 .mu.m on the surface of alumina, the average
particle size of which was 1.0 .mu.m. The voltage was applied while making
the substrate serve as the positive pole and using a stainless steel
electrode (0.5 t) to serve as the opposite pole at the bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C..+-.1.degree. C. for 90 minutes so
as to be hardened. The film thickness was 25 .mu.m and the density of the
metallized ceramic powder was 20 wt % at that time. Then, it was immersed
in 50 g/l of caustic soda at 40.degree. C. for 5 minutes so that the
photosensitive resin was separated. Subsequently, 10% hydrochloric acid
was used to remove, at 50.degree. C. for 7 minutes, the palladium film,
which was the catalyst, on the exposed portion. As a result, a fine
printed circuit board was manufactured.
The characteristics of the thus manufactured substrate were evaluated by
the same method according to Example 1.
EXAMPLE 1-6
The following circuit was evaluated: The circuit substrate having an
electrodeposited film in which the density of powder was 50 wt %, was
manufactured in a similar manner to the circuit of Example 1-1 with the
exception that a powder prepared by plating copper with a thickness of 2
.mu.m on the surface of titanium oxide, having an average particle size of
5 .mu.m was substituted for the nickel plated alumina powder.
EXAMPLE 1-7
The following circuit was evaluated:
A circuit substrate having an electrodeposited film in which the density of
powder was 55 wt %, was manufactured in a similar manner to the circuit of
Example 1-1 with the exception that a powder prepared by plating copper
with a thickness of 2 .mu.m on the surface of titanium oxide having an
average particle size of 0.5 .mu.m was substituted for the nickel plated
alumina powder.
EXAMPLE 1-8
A circuit substrate to be evaluated was manufactured in such a manner that
the electrically conductive paste according to Example 1-1 with the
exception that the electrolytic conditions were 70 V for 3 minutes and the
density of the metallized ceramic in the electrodeposited film was 25 wt
%.
EXAMPLE 1-9
A circuit substrate to be evaluated was manufactured in such a manner that
the electrically conductive paste according to Example 1-1 with the
exception that the electrolytic conditions were 180 V for 4 minutes and
the density of the metallized ceramic in the electrodeposited film was 75
wt %.
EXAMPLE 1-10
A circuit substrate having an electrodeposited film in which the density of
powder was 50 wt % was manufactured in a similar manner to the circuit of
Example 1-1 with the exception that metallized powder was used, prepared
by plating nickel with a thickness of 0.06 mm on the surface of alumina
having an average particle size of 1.mu.m, with electrolysis conducted at
170 V for 3 minutes.
EXAMPLE 1-11
The substrate with the resist pattern manufactured by the method according
to Example 1-1, was subjected to the same process according to Example 1-1
in electrically conductive paste prepared by dispersing 20 wt % of
desalinated water, 30 wt % of melamine acryl resin (trade name "Honey
Bright C-IL" manufactured by Honey Kasei), and 50 wt % of powder formed by
applying electroless gold plating to form a thickness of 0.2 .mu.m to the
surface of alumina, the average particle size of which was 1 .mu.m. In
consequence, a fine printed circuit board was obtained having an
electrodeposited film in which the density of the powder was 40 wt %.
REFERENCE EXAMPLE 1
As a reference example, the substrate according to Example 1-1 was
electrolyzed at 50 V for 2 minutes in electrically conductive paste
prepared by dispersing 25 wt % of desalinated water, 5 wt % of melamine
acryl resin (trade name "Honey Bright C-IL" manufactured by Honey Kasei)
and 70 wt % of powder formed by applying nickel plating to form a
thickness of 0.2 .mu.m to the surface of alumina the average particle size
of which was 1.0 .mu.m. In consequence, a fine printed circuit board was
manufactured having an electrodeposited film, in which the density of the
metallized ceramic was 15 wt % after it was hardened.
REFERENCE EXAMPLE 2
The substrate according to Example 1-1 was electrolyzed at 200 V for 2
minutes in electrically conductive paste prepared by dispersing 25 wt % of
desalinated water, 5 wt % of melamine acryl resin (trade name "Honey
Bright C-IL" manufactured by Honey Kasei) and 70 wt % of powder formed by
applying nickel plating to form a thickness of 0.2 .mu.m to the surface of
alumina the average particle size of which was 1.0 .mu.m. In consequence,
a fine printed circuit board was manufactured having an electrodeposited
film, in which the density of the metallized ceramic was 85 wt % after it
was hardened.
REFERENCE EXAMPLE 3
A circuit substrate having an electrodeposited film in which the density of
powder was 50 wt % was manufactured in a similar manner to Example 1-1
with the exception that the thickness of the copper plating layer, on the
surface of the alumina powder, was 0.02 .mu.m.
REFERENCE EXAMPLE 4
A circuit substrate having an electrodeposited film in which the density of
powder was 50 wt % was manufactured in a similar manner to Example 1-1
with the exception that the powder serving as the electrically conductive
powder was prepared by applying nickel plating to form a thickness of 0.2
.mu.m on the surface of the alumina having an average particle size of
0.07 .mu.m.
REFERENCE EXAMPLE 5
A circuit substrate having an electrodeposited film in which the density of
powder was 50 wt % was manufactured in a similar manner to Example 1-1
with the exception that the powder serving as the electrically conductive
powder was prepared by applying nickel plating to form a thickness of 0.2
.mu.m on the surface of the alumina having an average particle size of 8
.mu.m.
The circuit substrates according to Examples 1-2 to 1-11 and reference
examples 1 to 5 were evaluated similarly to Example 1-1. The results were
as shown in Table 1-2.
TABLE 1-2
______________________________________
Initial Value
Example Adhesion Specific Reistance (25.degree. C.)
______________________________________
1-2 100/100 5 to 6 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
1-3 100/100 6 to 7 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
1-4 100/100 5 to 6 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
1-5 100/100 3 to 4 .times. 10.sup.-4 [.OMEGA. .multidot. cm]
1-6 100/100 5 to 6 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
1-7 100/100 5 to 6 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
1-8 100/100 1 to 2 .times. 10.sup.-4 [.OMEGA. .multidot. cm]
1-9 96/100 5 to 6 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
1-10 100/100 3 to 4 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
1-11 100/100 7 to 8 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
Reference 60/100 1 to 2 .times. 10.sup.3 [.OMEGA. .multidot. cm]
Example 1
Reference 70/100 7 to 8 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
Example 2
Reference 100/100 1 to 2 .times. 10.sup.2 [.OMEGA. .multidot. cm]
Example 3
Reference 100/100 5 to 6 .times. 10.sup.1 [.OMEGA. .multidot. cm]
Example 4
Reference 100/100 2 to 3 .times. 10.sup.-4 [.OMEGA. .multidot. cm]
Example 5
______________________________________
As shown Table 1-2, according to the present invention, the physical
properties of the circuit substrate were significantly improved while
revealing a satisfactory reproducibility.
Furthermore, satisfactory results in the durability test were obtained
similarly to Example 1-1.
EXAMPLE 2-1
To a substrate having the resist pattern manufactured in Example 1-1, a
voltage of 170 V was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 35 wt % of desalinated water, 5 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei) and 30 wt % of powder formed by applying nickel 100 % plating to
form a thickness of 0.2 .mu.m on the surface of alumina, the average
particle size of which was 0.03 .mu.m, and 30 wt % of nickel powder, the
average size of which was 1 .mu.m, the voltage being applied while making
the substrate serve as the positive pole and using a stainless steel
electrode (0.5 t) to serve as the opposite pole at a bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C. .+-.1.degree. C. for 90 minutes
so as to be hardened. The film thickness was 25 .mu.m and the density of
the mixed powder substance was 50 wt % at that time. Then, it was immersed
in 50 g/l of caustic soda at 40.degree. C. for 5 minutes so that the
photosensitive resin was separated. Subsequently, ammonic alkaline copper
liquid was used to remove the copper plating film on the exposed portion
at 50.degree. C. for 7 minutes so that a fine printed circuit board was
obtained.
The characteristics of the thus manufactured circuit substrate were
evaluated by the same method according to Example 1-1.
EXAMPLE 2-2
To a substrate having the resist pattern manufactured in Example 1-2 a
voltage of 180 V was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 25 wt % of desalinated water, 5 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei), 40 wt % of nickel powder, the average size of which was 0.03 .mu.m
and 30 wt % of powder formed by applying nickel plating to form a
thickness of 0.5 .mu.m on the surface of alumina, the average particle
size of which was 1.0 .mu.m. The voltage was applied while making the
substrate serve as the positive pole and using a stainless steel electrode
(0.5 t) to serve as the opposite pole at the bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C..+-.1.degree. C. for 90 minutes so
as to be hardened. The film thickness was 30 .mu.m and the density of the
powder mixed substance was 60 wt % at that time. Then, it was immersed in
50 g/l of caustic soda at 40.degree. C. for 5 minutes so that the
photosensitive resin was separated. Subsequently, ammonic alkaline copper
liquid was used to remove the copper plating film on the exposed portion
at 50.degree. C. for 7 minutes so that a fine printed circuit board was
obtained.
EXAMPLE 2-3
To a substrate having the resist pattern manufactured in Example 1-3 a
voltage of 170 V was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 35 wt % of desalinated water, 5 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei), 30 wt % of copper powder, the average size of which was 0.03 .mu.m
and 30 wt % of powder formed by applying nickel plating to form a
thickness of 0.2 .mu.m on the surface of alumina, the average particle
size of which was 1.0.mu.. The voltage was applied while making the
substrate serve as the positive pole and using a stainless steel electrode
(0.5 t) to serve as the opposite pole at the bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C..+-.1.degree. C. for 90 minutes so
as to be hardened. The film thickness was 25 .mu.m and the density of the
powder mixed substance was 50 wt % at that time. Then, it was immersed in
50 g/l of caustic soda at 40.degree. C. for 5 minutes so that the
photosensitive resin was separated. Subsequently, ammonic alkaline copper
liquid was used to remove the copper plating film on the exposed portion
at 50.degree. C. for 7 minutes so that a fine printed circuit board was
obtained.
EXAMPLE 2-4
To a substrate having the resist pattern manufactured in Example 1-4 a
voltage of 120 V was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 27 wt % of desalinated water, 3 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei), 50 wt % of silver powder, the average particle size of which was
0.07 .mu.m and 20 wt % of powder formed by applying nickel plating to form
a thickness of 0.2 .mu.m on the surface of alumina, the average particle
size of which was 1.0 .mu.m. The voltage was applied while making the
substrate serve as the positive pole and using a stainless steel electrode
(0.5 t) to serve as the opposite pole at the bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C..+-.1.degree. C. for 90 minutes so
as to be hardened. The film thickness was 18 .mu.m and the density of the
powder mixed substance was 30 wt % at that time. Then, it was immersed in
an exclusive separation liquid for OMR at 40.degree. C. for 5 minutes so
that the photosensitive resin was separated. Subsequently, ammonic
alkaline copper liquid was used to remove the copper plating film on the
exposed portion at 50.degree. C. for 7 minutes so that a fine printed
circuit board was obtained.
EXAMPLE 2-5
To a substrate with the resist pattern used in Example 1-5 a voltage of 170
V was applied for 3 minutes in an electrically conductive paste prepared
by dispersing 35 wt % of desalinated water, 5 wt % of melamine acryl resin
(trade name "Honey Bright C-IL" manufactured by Honey Kasei), 30 wt % of
copper powder, the average particle size of which was 0.03 .mu.m and 30 wt
% of powder formed by applying nickel plating to form a thickness of 0.2
.mu.m on the surface of alumina the average particle size of which was 1.0
.mu.m, the voltage being applied while making the substrate to serve as
the positive pole and using a stainless steel electrode (0.5 t) to serve
as the opposite pole at the bath temperature of 23.degree. C. and pH value
of 8.5. Then, it was washed with water before being heated in an oven at
95.degree. C..+-.1.degree. C. for 90 minutes so as to be hardened. The
film thickness was 25 .mu.m and the density of the powder mixed substance
was 50 wt % at that time. Then, it was immersed in an exclusive separation
liquid for OMR at 40.degree. C. for 5 minutes so that the photosensitive
resin was separated. Subsequently, 10% hydrochloric acid was used to
remove the palladium film, which was the catalyst, on the exposed portion
at 50.degree. C. for 7 minutes, so that a fine printed circuit board was
obtained.
The circuit substrates according to Examples 2-1 to 2-5 were evaluated
similarly to Example 1-1. The results were as shown in Table 2.
TABLE 2
______________________________________
Initial Value
Example Adhesion Specific Reistance (25.degree. C.)
______________________________________
2-1 100/100 5 to 6 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
2-2 98/100 8 to 9 .times. 10.sup.-5 [.OMEGA. .multidot. cm]
2-3 100/100 5 to 6 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
2-4 100/100 3 to 4 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
2-5 100/100 5 to 6 .times. 10.sup.-6 [.OMEGA. .multidot. cm]
______________________________________
EXAMPLE 3-1
To a substrate with the resist pattern used in Example 1-1 a voltage of 170
V was applied for 3 minutes in an electrically conductive paste prepared
by dispersing 65 wt % of desalinated water, 5 wt % of melamine acryl resin
(trade name "Honey Bright C-IL" manufactured by Honey Kasei) and 30 wt %
of powder formed by applying electroless nickel plating to form a
thickness of 0.2 .mu.m on the surface of natural mica, the average
particle size of which was 2.0 .mu.m. The voltage was applied while making
the substrate serve as the positive pole and using a stainless steel
electrode (0.5 t) to serve as the opposite pole at the bath temperature of
23.degree. C. and pH value of 8.5. Then, it was washed with water before
being heated in an oven at 95.degree. C..+-.1.degree. C. for 90 minutes so
as to be hardened. The film thickness was 25 .mu.m and the density of the
metallized mica powder was 50 wt % at that time. Then, it was immersed in
50 g/l of caustic soda at 40.degree. C. for 5 minutes so that the
photosensitive resin was separated. Subsequently, ammonic alkaline copper
liquid was used to remove the copper plating film on the exposed portion
at 50.degree. C. for 7 minutes so that a fine printed circuit board was
obtained.
In order to evaluate the performance of the thus manufactured substrate,
the initial values and values after environmental testing of the specific
resistance, the surface resistance and the adhesion were measured. The
results are as shown in Table 3.
EXAMPLE 3-2
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-1 with the exception that the electrically
conductive paste was prepared by dispersing 45 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 30 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.2 .mu.m on the surface
the average particle size of which was 1.0 .mu.m and 20 wt % of powder
formed by applying electroless nickel plating to form a thickness of 0.2
.mu.m on the surface of natural mica, the average particle size of which
was 2.0 .mu.m.
EXAMPLE 3-3
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-1 with the exception that the electrically
conductive paste was prepared by dispersing 15 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 30 wt % of copper powder, the average
particle size of which was 0.03 .mu.m and 50 wt % of powder formed by
applying electroless nickel plating to form a thickness of 0.2 .mu.m on
the surface of natural mica, the average particle size of which was 2.0
.mu.m.
EXAMPLE 3-4
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 53 wt % was manufactured in a similar manner to
that according to Example 3-1 with the exception that the electrically
conductive paste was prepared by dispersing 35 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 30 wt % of copper powder, the average
particle size of which was 0.03 .mu.m, 20 wt % of powder formed by
applying electroless nickel plating to form a thickness of 0.2 .mu.m on
the surface of alumina, the average particle size of which was 1.0 .mu.m
and 10 wt % of powder formed by applying electroless nickel plating to
form a thickness of 0.2 .mu.m on the surface of natural mica, the average
particle size of which was 2.0 .mu.m.
EXAMPLE 3-5
To a substrate with the resist pattern manufactured in Example 1-2 a
voltage of 180 v was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 65 wt % of desalinated water, 5 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei) and 30 wt % of powder formed by applying electroless nickel plating
to form a thickness of 0.05 .mu.m on the surface of natural mica, the
average particle size of which was 1.5 .mu.m. The voltage was applied
while making the substrate serve as the positive pole and using a
stainless steel electrode (0.5 t) to serve as the opposite pole at a bath
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before being heated in an oven at 95.degree. C..+-.1.degree. C. for
90 minutes so as to be hardened. The film thickness was 30 .mu.m and the
density of the mixed powder substance was 60 wt % at that time. Then, it
was immersed in 50 g/l of caustic soda at 40.degree. C. for 5 minutes so
that the photosensitive resin was separated. Subsequently, ammonic
alkaline copper liquid was used to remove the copper plating film on the
exposed portion at 50.degree. C. for 7 minutes so that a fine printed
circuit board was obtained.
EXAMPLE 3-6
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 60 wt % was manufactured in a similar manner to
that according to Example 3-5 with the exception that the electrically
conductive paste was prepared by dispersing 35 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 20 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.5 .mu.m on the surface
of alumina, the average particle size of which was 1.0 .mu.m and 40 wt %
of powder formed by applying electroless nickel plating to form a
thickness of 0.05 .mu.m on the surface of natural mica, the average
particle size of which was 1.5 .mu.m.
EXAMPLE 3-7
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 60 wt % was manufactured in a similar manner to
that according to Example 3-5 with the exception that the electrically
conductive paste was prepared by dispersing 25 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei) and 40 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.05 .mu.m on the
surface of natural mica the average particle size of which was 1.5 .mu.m.
EXAMPLE 3-8
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 60 wt % was manufactured in a similar manner to
that according to Example 3-5 with the exception that the electrically
conductive paste was prepared by dispersing 25 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 40 wt % of nickel powder, the average size
of which was 0.03 .mu.m, 10 wt % of powder formed by applying electroless
nickel plating to form a thickness of 0.5 .mu.m on the surface of alumina
the average particle size of which was 1.0 .mu.m and 20 wt % of powder
formed by applying electroless nickel plating to form a thickness of 0.05
.mu.m on the surface of natural mica, the average particle size of which
was 1.5 .mu.m.
EXAMPLE 3-9
To a substrate with the resist pattern manufactured in Example 1-3 a
voltage of 170 V was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 35 wt % of desalinated water, 5 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei) and 60 wt % of powder formed by applying electroless nickel plating
to form a thickness of 0.2 .mu.m on the surface of natural mica, the
average particle size of which was 2 .mu.m. The voltage was applied while
making the substrate serve as the positive pole and using a stainless
steel electrode (0.5 t) to serve as the opposite pole at a bath
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before heated in an oven at 95.degree. C..+-.1.degree. C. for 90
minutes so as to be hardened. The film thickness was 25 .mu.m and the
density of the mixed powder substance was 50 wt % at that time. Then, it
was immersed in 50 g/l of caustic soda at 40.degree. C. for 5 minutes so
that the photosensitive resin was separated. Subsequently, ammonic
alkaline copper liquid was used to remove the copper plating film on the
exposed portion at 50.degree. C. for 7 minutes so that a fine printed
circuit board was obtained.
EXAMPLE 3-10
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-9 with the exception that the electrically
conductive paste was prepared by dispersing 35 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 30 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.2 .mu.m on the surface
of alumina, the average particle size of which was 1.0 .mu.m and 30 wt %
of powder formed by applying electroless nickel plating to form a
thickness of 0.2 .mu.m on the surface of natural mica, the average
particle size of which was 2 .mu.m.
EXAMPLE 3-11
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 51 wt % was manufactured in a similar manner to
that according to Example 3-9 with exception that the electrically
conductive paste was prepared by dispersing 50 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 20 wt % of copper powder, the average size
of which was 0.03 .mu.m and 25 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.2 .mu.m on the surface
of natural mica, the average particle size of which was 2 .mu.m.
EXAMPLE 3-12
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-9 with the exception that the electrically
conductive paste was prepared by dispersing 10 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 20 wt % of copper powder, the average
particle size of which was 0.03 .mu.m, 30 wt % of powder formed by
applying electroless nickel plating to form a thickness of 0.2 .mu.m on
the surface of alumina, the average particle size of which was 1.0 .mu.m
and 35 wt % of powder formed by applying electroless nickel plating to
form a thickness of 0.2 .mu.m on the surface of natural mica, the average
particle size of which was 2.0 .mu.m.
EXAMPLE 3-13
To a substrate with the resist pattern manufactured in Example 1-4 a
voltage of 120 V was applied for 3 minutes in an electrically conductive
paste prepared by dispersing 37 wt % of desalinated water, 3 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei) and 60 wt % of powder formed by applying electroless nickel plating
to form a thickness of 0.05 .mu.m on the surface of natural mica, the
average particle size of which was 2 .mu.m, the voltage being applied
while making the substrate serve as the positive pole and using a
stainless steel electrode (0.5 t) to serve as the opposite pole at a bath
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before being heated in an oven at 95.degree. C..+-.1.degree. C. for
90 minutes so as to be hardened. The film thickness was 18 .mu.m and the
density of the mixed powder substance was 30 wt % at that time. Then, it
was immersed in a separating liquid which was exclusive for the OMR at
40.degree. C. for 5 minutes so that the photosensitive resin was
separated. Subsequently, ammonic alkaline copper liquid was used to remove
the copper plating film on the exposed portion at 50.degree. C. for 7
minutes so that a fine printed circuit board was obtained.
EXAMPLE 3-14
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 30 wt % was manufactured in a similar manner to
that according to Example 3-13 with the exception that the electrically
conductive paste was prepared by dispersing 27 wt % of desalinated water,
3 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 20 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.2 .mu.m on the surface
of alumina, the average particle size of which was 1.0 .mu.m and 50 wt %
of powder formed by applying electroless nickel plating to form a
thickness of 0.05 .mu.m on the surface of natural mica, the average
particle size of which was 2.0 .mu.m.
EXAMPLE 3-15
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 30 wt % was manufactured in a similar manner to
that according to Example 3-13 with the exception that the electrically
conductive paste was prepared by dispersing 27 wt % of desalinated water,
3 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 40 wt % of silver powder, the average size
of which was 0.07 .mu.m and 30 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.05 .mu.m on the
surface of natural mica, the average particle size of which was 2.0 .mu.m.
EXAMPLE 3-16
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 30 wt % was manufactured in a similar manner to
that according to Example 3-13 with the exception that the electrically
conductive paste was prepared by dispersing 27 wt % of desalinated water,
3 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 40 wt % of silver powder, the average
particle size of which was 0.07 .mu.m, 20 wt % of powder formed by
applying electroless nickel plating to form a thickness of 0.2 .mu.m on
the surface of alumina, the average particle size of which was 1 0 .mu.m
and 10 wt % of powder formed by applying electroless nickel plating to
form a thickness of 0.05 .mu.m on the surface of natural mica, the average
particle size of which was 2.0 .mu.m.
EXAMPLE 3-17
To a substrate with the resist pattern manufactured in Example 1-5 a
voltage of 170 V was applied for 3 minutes in an electrically conductive
paste was prepared by dispersing 35 wt % of desalinated water, 5 wt % of
melamine acryl resin (trade name "Honey Bright C-IL" manufactured by Honey
Kasei) and 60 wt % of powder formed by applying electroless nickel plating
to form a thickness of 0.1 .mu.m on the surface of natural mica, the
average particle size of which was 1.0 .mu.m. The voltage was applied
while making the substrate serve as the positive pole and using a
stainless steel electrode (0.5 t) to serve as the opposite pole at a bath
temperature of 23.degree. C. and pH value of 8.5. Then, it was washed with
water before being heated in an oven at 95.degree. C..+-.1.degree. C. for
90 minutes so as to be hardened. The film thickness was 25 .mu.m and the
density of the mixed powder substance was 50 wt % at that time. Then, it
was immersed in 50 g/l of caustic soda at 40.degree. C. for 5 minutes so
that the photosensitive resin was separated. Subsequently, 10%
hydrochloric acid, at 50.degree. C. for 7 minutes, was used to remove the
palladium film, which was the catalyst, on the exposed portion. As a
result, a fine printed circuit board was manufactured.
EXAMPLE 3-18
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-17 with the exception that the electrically
conductive paste was prepared by dispersing 35 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 20 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.2 .mu.m on the surface
of alumina, the average particle size of which was 1.0 .mu.m and 40 wt %
of powder formed by applying electroless nickel plating to form a
thickness of 0.1 .mu.m on the surface of natural mica the average particle
size of which was 1.0 .mu.m.
EXAMPLE 3-19
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-17 with the exception that electrically
conductive paste was prepared by dispersing 35 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 30 wt % copper powder, the average particle
size of which was 0.03 .mu.m and 30 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.1 .mu.m on the surface
of natural mica, the average particle size of which was 1.0 .mu.m.
EXAMPLE 3-20
A fine circuit board having an electrodeposited film in which the density
of the powder mixture was 50 wt % was manufactured in a similar manner to
that according to Example 3-17 with the exception that the electrically
conductive paste was prepared by dispersing 35 wt % of desalinated water,
5 wt % of melamine acryl resin (trade name "Honey Bright C-IL"
manufactured by Honey Kasei), 30 wt % copper powder, the average particle
size of which was 0.03 .mu.m, 10 wt % of powder formed by applying
electroless nickel plating to form a thickness of 0.2 .mu.m on the surface
of alumina the average particle size of which was 1.0 .mu.m and 20 wt % of
powder formed by applying electroless nickel plating to form a thickness
of 0.1 .mu.m on the surface of natural mica, the average particle size of
which was 1.0 .mu.m. The performance of the thus manufactured fine printed
circuit boards according to Examples 3-1 to 3-20 were evaluated similarly
to 1-1. The results are shown in Tables 3-1 and 3-2.
TABLE 3-1
______________________________________
Initial Value After durability test
Specific at 55.degree. C. .times.
Ex- Resistance 95% RH .times. 1000 hr
ample Adhesion (25.degree. C.)
Adhesion
Specific Resistance
______________________________________
3-1 100/100 7 to 8 .times. 10.sup.-5
100/100
3% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-2 100/100 5 to 6 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-3 100/100 5 to 6 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-4 100/100 5 to 6 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-5 100/100 3 to 4 .times. 10.sup.-4
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-6 100/100 4 to 5 .times. 10.sup.-5
100/100
2% or Less
[ .OMEGA. .multidot. cm]
(Resistance Change)
3-7 100/100 1 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-8 100/100 5 to 6 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-9 100/100 5 to 6 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-10 100/100 4 to 5 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-11 100/100 5 to 6 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-12 100/100 5 to 6 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
______________________________________
TABLE 3-2
______________________________________
Initial Value After durability test
Ex- Specific at 55.degree. C. .times.
am- Resistance 95% RH .times. 1000 hr
ple Adhesion (25.degree. C.)
Adhesion
Specific Resistance
______________________________________
3-13 100/100 0.9 to 1 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-14 100/100 3 to 4 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-15 100/100 2 to 3 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-16 100/100 5 to 6 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-17 100/100 7 to 8 .times. 10.sup.-5
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-18 100/100 7 to 8 .times. 10.sup.-5
100/100
2% or Less
[ .OMEGA. .multidot. cm]
(Resistance Change)
3-19 100/100 3 to 4 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
3-20 100/100 4 to 5 .times. 10.sup.-6
100/100
2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
______________________________________
EXAMPLE 4-1
To a substrate having the resist pattern used in Example 1-1 a voltage of
170 V was applied for 3 minutes in an electrically conductive paste
prepared by dispersing 35 wt % of desalinated water, 5 wt % of melamine
acryl resin (trade name "Honey Bright C-IL" manufactured by Honey Kasei)
and 60 wt % of copper powder, the average particle size of which was 0.03
.mu.m. The voltage was applied while making the substrate serve as the
positive pole and using a stainless steel electrode (0.5 t) to serve as
the opposite pole at a bath temperature of 23.degree. C. and pH value of
8.5. Then, it was washed with water before being heated in an oven at
150.degree. C..+-.1.degree. C. for 90 minutes so as to be hardened. The
film thickness was 25 .mu.m and the density of the metal powder was 50 wt
% at that time. Then, it was immersed in 50 g/l of caustic soda at
40.degree. C. for 5 minutes so that the photosensitive resin was
separated. Subsequently, ammonic alkaline copper liquid was used to remove
the copper plating film on the exposed portion at 50.degree. C. for 7
minutes so that a fine printed circuit board was obtained.
EXAMPLE 4-2
To a substrate having the resist pattern used in Example 1-2 a voltage of
180 V was applied for 3 minutes in an electrically conductive paste
prepared by dispersing 25 wt % of desalinated water, 5 wt % of melamine
acryl resin (trade name "Honey Bright C-IL" manufactured by Honey Kasei)
and 70 wt % of nickel powder, the average particle size of which was 0.03
.mu.m. The voltage was applied while making the substrate serve as the
positive pole and using a stainless steel electrode (0.5 t) to serve as
the opposite pole at a bath temperature of 23.degree. C. and pH value of
8.5. Then, it was washed with water before being heated in an oven at
145.degree. C..+-.1.degree. C. for 90 minutes so as to be hardened. The
film thickness was 30 .mu.m and the density of the metal powder was 60 wt
% at that time. Then, it was immersed in 50 g/l of caustic soda at
40.degree. C. for 5 minutes so that the photosensitive resin was
separated. Subsequently, ammonic alkaline copper liquid was used to remove
the copper plating film on the exposed portion at 50.degree. C. for 7
minutes so that a fine printed circuit board was obtained.
EXAMPLE 4-3
To a substrate having the resist pattern used in Example 1-3 a voltage of
170 V was applied for 3 minutes in an electrically conductive paste
prepared by dispersing 15 wt % of desalinated water, 5 wt % of melamine
acryl resin (trade name "Honey Bright C-IL" manufactured by Honey Kasei)
and 80 wt % of copper powder, the average particle size of which was 0.03
.mu.m. The voltage was applied while making the substrate serve as the
positive pole and using a stainless steel electrode (0.5 t) to serve as
the opposite pole at a bath temperature of 23.degree. C. and pH value of
8.5. Then, it was washed with water before being heated in an oven at
145.degree. C..+-.1.degree. C. for 90 minutes so as to be hardened. The
film thickness was 25 .mu.m and the density of the metal powder was 50 wt
% at that time. Then, it was immersed in 50 g/l of caustic soda at
40.degree. C. for 5 minutes so that the photosensitive resin was
separated. Subsequently, ammonic alkaline copper liquid was used to remove
the copper plating film on the exposed portion at 50.degree. C. for 7
minutes so that a fine printed circuit board was obtained.
EXAMPLE 4-4
To a substrate having the resist pattern used in Example 1-4 a voltage of
120 V was applied for 3 minutes in an electrically conductive paste
prepared by dispersing 47 wt % of desalinated water, 3 wt % of melamine
acryl resin (trade name "Honey Bright C-IL" manufactured by Honey Kasei)
and 50 wt % of silver powder, the average particle size of which was 0.07
.mu.m. The voltage was applied while making the substrate serve as the
positive pole and using a stainless steel electrode (0.5 t) to serve as
the opposite pole at a bath temperature of 23.degree. C. and pH value of
8.5. Then, it was washed with water before being heated in an oven at
145.degree. C..+-.1.degree. C. for 90 minutes so as to be hardened. The
film thickness was 18 .mu.m and the density of the metal powder was 30 wt
% at that time. Then, it was immersed in an exclusive separating liquid
for the OMR at 40.degree. C. for 5 minutes so that the photosensitive
resin was separated. Subsequently, ammonic alkaline copper liquid was used
to remove the copper plating film on the exposed portion at 50.degree. C.
for 7 minutes so that a fine printed circuit board was obtained.
EXAMPLE 4-5
To a substrate having the resist pattern used in Example 1-5 a voltage of
170 V was applied for 3 minutes in an electrically conductive paste
prepared by dispersing 35 wt % of desalinated water, 5 wt % of melamine
acryl resin (trade name "Honey Bright C-IL" manufactured by Honey Kasei)
and 60 wt % of copper powder, the average particle size of which was 0.03
.mu.m. The voltage was applied while making the substrate serve as the
positive pole and using a stainless steel electrode (0.5 t) to serve as
the opposite pole at a bath temperature of 23.degree. C. and pH value of
8.5. Then, it was washed with water before being heated in an oven at
145.degree. C..+-.1.degree. C. for 90 minutes so as to be hardened. The
powder had been treated with a surface active agent. The film thickness
was 25 .mu.m and the density of the metal powder was 50 wt % at that time.
Then, it was immersed in 50 g/l of caustic soda at 40.degree. C. for 5
minutes so that the photosensitive resin was separated. Subsequently, 10%
hydrochloric acid was used to remove, at 50.degree. C. for 7 minutes, the
palladium film, which was the catalyst, on the exposed portion. As a
result, a fine printed circuit board was manufactured.
The characteristics of the thus manufactured substrate according to
Examples 4-1 to 4-5 were evaluated by the same method according to Example
1-1. The results are shown in Table 4.
TABLE 4
______________________________________
Initial Value After durability test
Specific at 55.degree. C. .times.
Ex- Resistance 95% RH .times. 1000 hr
ample Adhesion (25.degree. C.)
Adhesion
Specific Resistance
______________________________________
4-1 98/100 2 to 3 .times. 10.sup.-4
98/100 Raised by 5%
[.OMEGA. .multidot. cm]
(Resistance Change)
4-2 96/100 1 to 2 .times. 10.sup.-3
95/100 Raised by 4%
[.OMEGA. .multidot. cm]
(Resistance Change)
4-3 100/100 3 to 4 .times. 10.sup.-4
97/100 Raised by 4%
[.OMEGA. .multidot. cm]
(Resistance Change)
4-4 98/100 3 to 4 .times. 10.sup.-3
98/100 Raised by 3%
[.OMEGA. .multidot. cm]
(Resistance Change)
4-5 98/100 3 to 4 .times. 10.sup.-4
98/100 2% or Less
[.OMEGA. .multidot. cm]
(Resistance Change)
______________________________________
Although the invention has been described in its preferred form with a
certain degree of particularly, it is understood that the present
disclosure is not limited to the examples set forth herein. The details of
construction and the combination and arrangement of parts may be varied
without departing from the spirit and the scope of the invention as
hereinafter claimed.
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